U.S. patent number 6,986,230 [Application Number 10/649,344] was granted by the patent office on 2006-01-17 for foldable support structure with hinged wall members.
This patent grant is currently assigned to Eagle Development Corporation. Invention is credited to Mark Brauer, Patrick M. Hamilton, Paul Miklautsch, Shaohui Qiu, Ralph L. Schipani, Richard K. Strayer.
United States Patent |
6,986,230 |
Schipani , et al. |
January 17, 2006 |
Foldable support structure with hinged wall members
Abstract
A foldable truss member suitable for commercial displays
includes a plurality of side members that are hingedly connected
together. The side members include support members and bridging
members having extensions. The side members are joined into a
foldable structure with a hinge member between the support member
and extensions of adjacent side members. The truss includes
frictional hinge surfaces that hold the truss member in a deployed
configuration. A display structure can be formed by connecting a
locking frame between two truss members.
Inventors: |
Schipani; Ralph L. (Edina,
MN), Strayer; Richard K. (Andover, MN), Brauer; Mark
(Minneapolis, MN), Miklautsch; Paul (Shakopee, MN),
Hamilton; Patrick M. (Golden Valley, MN), Qiu; Shaohui
(Minneapolis, MN) |
Assignee: |
Eagle Development Corporation
(Minneapolis, MN)
|
Family
ID: |
46299853 |
Appl.
No.: |
10/649,344 |
Filed: |
August 27, 2003 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20040111999 A1 |
Jun 17, 2004 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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10186285 |
Jun 28, 2002 |
6715255 |
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Current U.S.
Class: |
52/694; 211/199;
52/646 |
Current CPC
Class: |
A47F
5/13 (20130101); E04C 3/005 (20130101); E04C
3/09 (20130101); E04C 2003/0495 (20130101) |
Current International
Class: |
E04C
3/02 (20060101) |
Field of
Search: |
;52/637,638,645,646,648.1,694,652.1,653.1,653.2 ;211/195,198,199
;446/115,116 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Slack; Naoko
Attorney, Agent or Firm: Altera Law Group, LLC
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of non-provisional application Ser.
No. 10/186,285, filed Jun. 28, 2002 now U.S. Pat. No. 6,715,255.
Claims
What is claimed is:
1. A foldable truss member comprising: a plurality of adjacently
connected side members together forming a peripheral boundary of
the truss member, each side member comprising: an elongated support
member having a side surface; a bridging member hingedly connected
to the side surface of the support member at an attachment point of
the support member, the bridging member having an extension at an
edge of the bridging member opposite the attachment point; and a
plurality of hinge members pivotally joining the extension of each
side member to a support member of an adjacent side member, each
hinge member having surfaces frictionally engaging the bridging
members and a channel for said bridging member and wherein said
support member forms a pad of the hinge together with said channel
which captures said bridging member, thereby allowing relative
rotation of adjacent side members, a plurality of edges between
adjacent side members defining a plurality of corners of the truss
member.
2. A foldable truss member, comprising: a plurality of side members
each having at least four sides including two adjacent side edges,
the side members adjacently arranged so that the side edges of the
four adjacently arranged sides define a closed shape; and a
plurality of hinges affixed to each of the two adjacent edges of
each side member, the hinges allowing relative rotation between
adjacently arranged side members so that the side member means are
foldable into a substantially flat assembly, the side edges of the
side member means defining a plurality of corners of the truss
member, wherein the hinges comprise surfaces frictionally engaging
the bridges, and the hinges are fixedly connected to the side
members.
3. A method of operating a foldable truss member capable of moving
from a substantially flat to an open deployed position, comprising:
adjacently bridging a plurality of side members to form a
peripheral boundary for each of the truss members, each of the side
members including an elongated edge hingedly attached to an
adjacent side member, the elongated edges of the side members
defining a plurality of corners of the truss member; rotating the
adjacent side members about the elongated edges to put the side
members of the truss member in a deployed configuration; and
creating a variable rotational resistance between said side members
so that it is necessary to overcome a holding force when said truss
member is in a deployed position and is being moved toward a folded
position, to generally maintain said truss in a deployed
position.
4. A foldable truss member moveable between a substantially folded
and open deployed positions, comprising: a plurality of adjacently
connected side members together forming a peripheral boundary of
the truss member, each side member comprising: an elongated support
member having a side surface; a bridging member hingedly connected
to the side surface at an attachment point of the support member, a
plurality of hinge members pivotally joining the bridging member to
the support member and an adjacent side member, each hinge member
allowing relative rotation of the side members at least one of said
hinge members having a center portion configured to tend to
maintain said bridging member in a position corresponding to the
deployed position of said truss member by virtue of said hinge
member providing less resistance to rotation in said center portion
and greater resistance to rotation elsewhere, so that when said
truss system is deployed, it will tend to stay In a deployed
state.
5. The truss member according to claim 4, wherein the hinge members
comprise surfaces frictionally engaging the bridging members and
wherein said frictional engagement is variable across said hinge
member's surface.
6. The truss member according to claim 4, wherein the hinge members
comprise a block member affixed to said support member having a
channel therethrough, said channel being sized to frictionally
receive a movable bridging member.
7. The truss member according to claim 4, wherein the block member
includes a channel for said bridging member and where said channel
includes at least one filleted inner surface which contacts said
bridging member.
8. The truss member according to claim 7 wherein said channel
includes predetermined bend radius, and where said bridging member
includes a curved portion sized to be received within said channel
and having a predetermined bend radius different from said channel
radius, thereby creating frictional interference between said
channel and said bridging member.
9. The truss member according to claim 4, wherein the block member
includes a generally U-shaped channel for said bridging member and
where said channel is radiused to provide rotational resistance
between said channel and said bridging member.
10. The truss member according to claim 4 wherein said block member
includes a hinge channel therethrough and plurality of surfaces
along said channel including a central surface and a flared
surface.
11. The truss member according to claim 10 wherein said flared
surface includes a partially flattened region positioned such that,
when said truss is in its deployed state, said a portion of said
bridging member will be urged into said partially flattened
region.
12. The truss member according to claim 4 wherein block includes a
channel having an inner surface and at least one side surface
extending from said channel, and wherein said side surface has a
trough section and flared sections on either side thereof, and
wherein said side surface is configured to urge said bridging
member into said trough when in said deployed state.
13. The truss member according to claim 4 wherein said trough
section and said bridge member are configured to provided feedback
resistance whenever said truss is moved from a deployed state
toward a folded state.
14. The truss member according to claim 4 wherein said hinge
members include primary hinge members and secondary hinge members,
said primary hinge members configured to urge said bridging members
to a position corresponding to the deployed position of said truss
member, and said secondary hinge member being free swinging.
15. The truss member of claim 14 wherein said primary and secondary
hinge members are apportioned to tune the deployment force of said
hinge members.
16. The truss member of claim 14 wherein said primary and secondary
hinge members are commingled on the truss member to permit
adjustment of deployment force of said hinge members.
17. A foldable truss member moveable between a substantially folded
and open deployed positions, comprising: a plurality of adjacently
connected side members together forming a peripheral boundary of
the truss member, each side member comprising: an elongated support
member having a side surface; a bridging member hingedly connected
to the side surface at an attachment point of the support member,
at least one hinge member pivotally joining the bridging member to
the support member and an adjacent side member, said hinge member
allowing relative rotation of the side members said at least one
hinge member having a center portion being configured to tend to
maintain said bridging member in a position corresponding to the
deployed position of said truss member by virtue of said member
providing less resistance to rotation in said center portion and
greater resistance to rotation elsewhere, so that when said truss
system is deployed, it will tend to stay in a deployed state.
18. A foldable truss member moveable between a substantially folded
and open deployed positions, comprising: a plurality of adjacently
connected side members together forming a peripheral boundary of
the truss member, each side member comprising: an elongated support
member having a side surface; a bridging member hingedly connected
to the side surface at an attachment point of the support member,
at least one first and second hinge members pivotally joining the
bridging member to the support member and an adjacent side member,
said hinge member allowing relative rotation of the side members
said at least one first hinge member having a center portion being
configured to tend to maintain said bridging member in a position
corresponding to the deployed position of said truss member by
virtue of said hinge member providing less resistance to rotation
in said center portion and greater resistance to rotation elsewhere
so that when said truss system is deployed, it will tend to stay in
a deployed state and said at least one second hinge member being
substantially free-swinging.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to portable support structures for
use in temporary fixtures such as trade shows and conventions, and
particularly to a portable folding truss system having hinged side
elements.
2. Description of Related Art
Commercial displays such as those used in trade show booths require
strong structures that can be easily transported and configurable
in a wide variety of forms. Such structures need to be lightweight,
portable, and able to be quickly set up and broken down.
Prior art solutions have utilized truss members with folding
elements that utilize rigid wall members coupled with rotatable
wall members. The rotatable side members allow the truss to
collapse. The trusses include internal diagonal pivoting members
that serve to lock the truss into an open position. Although useful
in some applications, this approach has deficiencies.
Using differently designed rigid and rotatable wall members as in
prior art solutions increases the inventory of piece parts needed
to build the truss, thereby making the truss more complicated and
expensive to manufacture. Also, the non-symmetry of the assembled
structure (due to the non-rigidity of the rotatable wall members)
gives such a truss non-uniform load bearing characteristics when
deployed horizontally. Therefore, if the user is not careful and/or
cognizant of the requirement for a certain orientation, a structure
according to the prior art design might be deployed in an unsafe
manner with potentially catastrophic results.
It can be seen that there is a need for a collapsible/foldable
truss member that is strong, easily fabricated and assembled into a
temporary or permanent structure for a commercial display or other
structural application. Further, a truss member that can be
configured to provide horizontal support regardless of the truss
member's orientation is also needed. The present invention fulfills
these and other needs, and addresses other deficiencies of prior
art implementations.
SUMMARY OF THE INVENTION
To overcome the limitations in the prior art described above, and
to overcome other limitations that will become apparent upon
reading and understanding the present specification, the present
invention discloses a portable support structure for use in a
temporary or permanent display such as trade shows and conventions
and stores, and particularly a portable folding truss system having
locking wall members and locking hinge elements.
An apparatus in accordance with the principles of the present
invention includes a foldable truss member including a plurality of
adjacently connected side members together forming a peripheral
boundary of the truss member. Each side member including an
elongated support member having a side surface and a bridging
member hingedly connected to the side surface of the support member
at an attachment point of the support member. The bridging member
having an extension at an edge of the bridging member opposite the
attachment point. The side member also includes a plurality of
hinge members pivotally joining the bridging member to the support
member and an adjacent side member. Each hinge member allowing
relative rotation of the side members.
Other embodiments of a system in accordance with the principles of
the invention may include alternative or optional additional
aspects. One such aspect of the present invention is that each
bridging member also includes a sawtooth-shaped member having a
first and second set of oppositely disposed peaks. The first set of
peaks hingedly attached to the attachment point of the support
member. The extensions of each bridging member including the second
set of peaks.
Another aspect of the present invention is that the hinge members
include surfaces frictionally engaging the bridging members.
Another apparatus in accordance with the principles of the present
invention includes a foldable truss member including a plurality of
adjacently connected side members together forming a peripheral
boundary of the truss member. Each side member including an
elongated support member having a side surface and a bridging
member hingedly connected to the side surface of the support member
at an attachment point of the support member. The bridging member
having an extension at an edge of the bridging member opposite the
attachment point. The side member also including a plurality of
hinge members pivotally joining the extension of each side member
to a support member of an adjacent side member. Each hinge member
allowing relative rotation of adjacent side members. A plurality of
edges between adjacent side members define a plurality of corners
of the truss member.
Another aspect of the present invention is that each bridging
member also includes a sawtooth-shaped member having a first and
second set of oppositely disposed peaks. The first set of peaks
hingedly attached to the attachment point of the support member and
the extensions of each bridging member comprising the second set of
peaks.
Another aspect of the present invention is that the hinge members
include surfaces frictionally engaging the bridging members.
Another apparatus in accordance with the principles of the present
invention includes a foldable truss member including a plurality of
side member means. Each side member means including a receiving
means located at a lower edge of the side member means. The side
member means adjacently arranged so that the lower edges of the
adjacently arranged side member means form a closed shape having a
plurality of corners. The side member means also including a
plurality of hinging means connecting adjacently arranged side
member means. The hinging means allowing relative rotation between
adjacently arranged side member means so that the side member means
are foldable into a substantially flat assembly.
Another aspect of the present invention is that the truss member
also includes bridging means hingedly connecting at least two side
member means.
Another aspect of the present invention is that the bridging means
include a sawtooth-shaped member having a first and second set of
oppositely disposed peaks. The first set of peaks hingedly attached
to the attachment point of the side member means and the extensions
of each bridging means hingedly connecting the second set of peaks
to an adjacent side member means.
Another aspect of the present invention is that the hinge means
include surfaces frictionally engaging the bridging means and the
hinge means are fixedly connected to the side member means.
Another apparatus in accordance with the principles of the present
invention includes a foldable truss member including a plurality of
side member means each including a lower edge and two side edges.
The side member means adjacently arranged so that the lower edges
of the adjacently arranged side member means form a closed shape.
The side member means also include a plurality of hinging means
connected between the side edges of the adjacently arranged side
member means. The hinging means allowing relative rotation between
adjacently arranged side member means so that the side member means
are foldable into a substantially flat assembly. The side edges of
the side member means defining a plurality of corners of the truss
member.
Another aspect of the present invention is that the truss member
also includes bridging means hingedly connecting at least two side
member means.
Another aspect of the present invention is that the bridging means
include a sawtooth-shaped member having a first and second set of
oppositely disposed peaks. The first set of peaks hingedly attached
to the attachment point of the side member means and the extensions
of each bridging means hingedly connecting the second set of peaks
to an adjacent side member means.
Another aspect of the present invention is that the hinge means
include surfaces frictionally engaging the bridging means and the
hinge means are fixedly connected to the side member means.
A method in accordance with the principles of the present invention
includes a method of assembling a truss member including adjacently
coupling a plurality of side members to form a peripheral boundary
for each of the truss members. Each of the side members including
an elongated edge hingedly attached to a bridging member. The
bridging members hingedly attached to adjacent side members. The
method also includes relatively rotating side members and the
bridging members to place the side members of the truss member in a
deployed configuration.
Another aspect of the present invention is that the method also
includes relatively rotating the adjacent side members about the
elongated edges with a folding force sufficient to overcome the
holding force of a plurality of hinge members and rotating the side
members to put the truss member in a folded configuration.
Another aspect of the present invention is that the method also
includes at least two adjacent side members are hingedly connected
together via a plurality of hinge members connecting the side
members to a bridging member.
A method in accordance with the principles of the present invention
includes a method of assembling a truss member including adjacently
coupling a plurality of side members to form a peripheral boundary
for each of the truss members. Each of the side members including
an elongated edge hingedly attached to an adjacent side member. The
elongated edges of the side members defining a plurality of corners
of the truss member. The method also including rotating the
adjacent side members about the elongated edges to put the side
members of the truss member in a deployed configuration and
rotating the side members to overcome a holding force in the
deployed configuration of the truss member to prevent further
relative rotation of the side members.
Another aspect of the present invention is that the method also
includes relatively rotating the side members to overcome a folding
force sufficient to overcome the holding force of a plurality of
hinge members and rotating the adjacent side members to place the
truss member in a folded configuration.
Another aspect of the present invention is that the method also
includes adjacent side members are connected via a plurality of
hinge members which connect a plurality of bridging members between
adjacent side members.
The foregoing objects, advantages and distinctions of the
invention, among others, are obtained in a presently preferred
construction that provides a portable foldable truss system having
locking wall members and locking hinge elements.
These and various other advantages and features of novelty which
characterize the invention are pointed out with particularity in
the claims annexed hereto and form a part hereof. However, for a
better understanding of the invention, its advantages, and the
objects obtained by its use, reference should be made to the
drawings which form a further part hereof, and to accompanying
descriptive matter, in which there are illustrated and described
specific examples of an apparatus in accordance with the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings in which like reference numbers
represent corresponding parts throughout:
FIG. 1 illustrates a perspective view of a foldable truss according
to an embodiment of the present invention;
FIG. 2 illustrates a side view of a side member according to an
embodiment of the present invention;
FIG. 3A illustrates a perspective view of a hinge member according
to an embodiment of the present invention;
FIG. 3B illustrates a perspective view of the hinge member
interacting with a bridging member extension according to an
embodiment of the present invention;
FIG. 3C illustrates a perspective view of an alternate hinge member
illustrating locking features according to an embodiment of the
present invention;
FIG. 4 illustrates an end view of the foldable truss member showing
a partially folded configuration according to an embodiment of the
present invention;
FIG. 5 illustrates a perspective view of a locking frame according
to an embodiment of the present invention; and
FIG. 6 illustrates a partial side view of a display structure
according to an embodiment of the present invention.
While the invention is amenable to various modifications and
alternative forms, specifics thereof have been shown by way of
example in the drawings and will be described in detail herein. It
is to be understood, however, that the intention is not to limit
the invention to the particular embodiments described. On the
contrary, the invention is intended to cover all modifications,
equivalents, and alternatives falling within the scope of the
invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
In the following description of the illustrated embodiments,
references is made to the accompanying drawings which form a part
hereof, and in which is shown by way of illustration, various
embodiments in which the invention may be practiced. It is to be
understood that other embodiments may be utilized, and structural
and functional changes may be made without departing from the scope
of the present invention.
The present invention discloses a portable support structure for
use in a temporary or permanent display such as trade shows and
conventions and stores, and particularly a portable folding truss
system having locking wall members and locking hinge elements.
FIG. 1 illustrates a perspective view of a foldable truss according
to an embodiment of the present invention. In FIG. 1, a truss
member 100 includes a plurality of side members 102. The side
members 102 are adjacently connected to form a peripheral boundary
of the truss member 100 such that the lower edges 101 of the side
members 102 form a closed shape such as a rectangle or a square.
The side members 102 include a support member 104 and a bridging
member 106 connected by hinge members 108. The bridging members 106
are formed of a continuous length of tubular material formed into a
generally planar sawtooth or V-shape. The bridging members 106
include one or more extensions 107 located at an edge opposite
where the bridging members 106 join the support members 104. The
extensions 107 are located at distal angular corners of the
sawtooth shape. The truss member 100 is formed by joining multiple
side members 102 and bridging members 106 using a plurality of
hinge members 108.
The hinge members 108, shown in FIG. 1, are fixed to each support
member 104 and pivotally join the bridging members 106 to adjacent
support members 104. The hinge members 108 allow relative rotation
of adjacent side members 102 while preventing the adjacent side
members 102 from separating. As illustrated in FIG. 1, the truss
member 100 contains four, pivotable, side members 102, thereby
allowing the truss member 100 to be folded substantially flat for
storage and shipment.
The hinge members 108 can be configured to hold the truss member
100 in a deployed configuration. In a deployed configuration, the
side members 102 are rotated to an orientation so that the truss
member 100 takes on the shape desired for the intended
installation. Typically, this shape is a rectangle or square (as
exemplified in FIG. 1) although it may be desired to make the
deployed shape a parallelogram, triangle, or other polygon. The
hinge member 108 may include locking or frictional features that
retain the side members 102 in position once the side members 102
are oriented in the deployed configuration. Details of the locking
and/or frictional features of the hinge members 108 will be
described at a later point herein below.
The foldable truss member 100 may also be made to form a rigid
support structure through use of a locking frame 110 or by other
means such as cross member braces detailed elsewhere herein. The
locking frame 110 is a rigid assembly with locking members 112 that
interface with two or more support members 104 of the truss member
100 in a deployed configuration. The example shown in FIG. 1 shows
a square or rectangular locking frame 110 with a locking member 112
at each corner.
The locking members 112 interface with receiving ends 114 of the
support members 104. The locking members 112 are inserted into the
receiving ends 114 to retain the truss member 100 in the deployed
orientation. The receiving ends 114 may be formed as recesses or
open ends of the support members 104. The locking members 112
typically extend from a top and bottom side of the locking frame
110, enabling multiple truss members 100 to be assembled end-to-end
into a rigid support structure.
It is appreciated that alternate forms of a locking frame 110 can
be used with a truss member 100 according to the present invention.
Alternate structural elements known in the art can used to couple
two or more side members 102 to make the truss member 100 rigid.
For example, the locking frame 110 can be fabricated of a plate
material having protruding locking members 112, or as a bar with
two locking members 112 at each end. The locking members 112 can be
made to encompass the receiving ends 114 and thereby allow the use
of solid support members 104.
Turning now to FIG. 2, a side view of an embodiment of a side
member 102 is shown. The truss member 100 is formed by adjacently
connecting a plurality of side members 102 to form the outer walls
of the truss member. Note that the side members 102 may be made
substantially identical. Not only does this reduce the number of
fabricated parts required to manufacture the truss member 100, it
is also appreciated that a truss member 100 utilizing substantially
identical side members will have symmetric transverse load
characteristics (i.e. loads that are perpendicular to the
longitudinal axis of the truss member). This makes such a truss
member 100 ideal for horizontal installations, as there is no need
for a preferred orientation of the side members 102.
The side member 102 is formed by attaching a bridging member 106 to
a support member 104 with hinge members 108. The support member 104
is preferably formed from a tubular material, although it need not
be hollow. Any cross-sectional shape of the support member 104 is
appropriate, although a rectangular, square, or round cross
sectional shape is typically the most useful. The illustrated
support member 104 is formed from a square tube material.
The bridging member 106 is fixed to one side of the support member
104 at attachment points 204 with hinge members 108. The bridging
member 106 can be tubular or a bar member bent into a sawtooth
shape and attached with hinge members 108 to the support member
104. It is appreciated that the bridging member 106 can
alternatively be formed from various elements, including a pattern
cut from a sheet material or any elongated member (e.g. bar) formed
into the desired shape. Further, although the bridging members 106
and other truss member components are typically made from metals
(e.g. steel, aluminum, copper, brass, zinc, etc), the components
can also be made alternate materials such as woods, plastics,
carbon fiber, corrugated cardboard and composite materials.
The bridging member 106 includes extensions 107 that interface with
hinge members 108 of an adjacent side member 102. The hinge members
108 are attached to the support member 104 at a location on the
support member 104 generally in alignment with the bridging member
extensions 107. The hinge members 108 are typically removably, as
opposed to being permanently attached, thereby making assembly
easier and allowing for assembly, disassembly, and re-assembly of
the truss member 100 as desired.
FIG. 3A shows an embodiment of an attachable hinge member 108. The
hinge member 108 includes a mounting surface 302 with mounting
holes 305. The mounting holes 305 align with holes on the support
member 104 (not shown). The mounting holes 305 are adapted to
receive fasteners, such as bolts, screws, rivets, locking pins,
etc. The hinge member 108 includes a hinge channel 306 for
receiving the extension 107 of a bridging member 106 therethrough.
The hinge channel 306 is disposed through a portion of the mounting
surface 302 and includes flared ends 308 that allow a generally
curved extension 107 to freely rotate through 180 degrees within
the hinge channel 306.
The hinge member 108 may include features that allow the truss
member 100 to maintain its deployed configuration during
installation. These features are detailed in FIGS. 3B and 3C. In
FIG. 3B, a portion of a bridging member 106 is shown in solid line
with the extension 107 located within the hinge channel 306
oriented in a typical deployed configuration of the truss member
100. The orientations of the bridging member 106 corresponding to
the folded configurations of the truss member 100 are shown using
broken lines. Between the orientations illustrated are intermediate
configurations, where the bridging member 106 is located when truss
member 100 is being folded or deployed. In one embodiment, the
hinge member 108 includes features that hold the extension 107 in a
deployed configuration by using either friction and/or elastic
deformation of the extension 107 to resist rotation of the bridging
member 106.
An example of hinge features that resist rotation of the bridging
member 106 are shown in FIG. 3C. In FIG. 3C, the flared end 308 of
the hinge channel 306 includes three portions of differing
geometry. These portions include one or more terminal portions 310,
a center portion 312 and one or more intermediate portions 314.
These portions 310, 312, 314 correspond to the orientation of the
extension 107 within the hinge member 106 when the truss member 100
is in the folded, deployed, and intermediate configurations,
respectively. The terminal portions 310 are designed to offer
little or no interference with the extension 107, thereby allowing
easy rotation of side members 102 in the folded configuration. The
intermediate portions 314 offer varying resistance where the
intermediate portions 314 are adjacent the center portion 312. The
center portion 312 typically offers some resistance to rotation of
the extension 107, although preferably less resistance than the
intermediate portions 314. Having less resistance at the center
portion 312 gives the user feedback that the truss member 100 has
attained the deployed configuration, because the extensions 107
will "snap" into the center portion 312.
The portions 310, 312, 314 of the hinge member 108 can offer
changing resistance to rotation of the extension by various means.
In the example of FIG. 3C, the portions 310, 312, and 314 are
formed by fillets or small grooves that form the hinge channel 308.
It is appreciated that forming a fillet radius different than the
inner bend radius of the extension 107 will cause the fillets to
ride or rub (frictionally interfere) at contact points against
portions of the extension 107. Also, the portions 310, 312, 314 of
the hinge member 108 are arrayed generally radially about a rounded
portion 318 of the hinge channel 306. The rounded portion 318 has a
substantially constant semicircular profile throughout the hinge
channel 306 in order to effectively restrain the side members 102
during deployment of the truss member 100. The portions 310, 312,
314 of the hinge member 108 may have varying shapes and be located
at varying radial distances from the rounded portion 318 in order
to increase or decrease interference with the extension 107. For
example, as shown in FIG. 3C, the intermediate portions 314 are
located radially closer to the rounded portion 318 than the other
portions 310, 312 and are somewhat flattened, thereby giving the
flared end 308 a peaked appearance. In this way, the intermediate
portion 314 causes an increase in friction and/or elastic
deformation of the extension 107, thereby resisting rotation of the
extension 107.
Truss members 100 may be constructed that have a large number of
extensions 107 along the side members 102. In this case, it may be
desirable to include a mixture of hinge members 108 alternately
configured according to both the configurations shown in FIG. 3A
and FIG. 3C. This allows the folding action of the truss assembly
100 to be "tuned", so that holding forces are not excessive.
A truss member 100 may be assembled by locating the extensions 107
of a first side member 102 within the channels 306 of associated
hinge members 108. The associated hinge members 108 are then
attached to the support member 104 of a second side member 102,
trapping the extensions 107 of the first side member 102 between
the associated hinge members 108 and the support member 104 of the
second side member 102. This process is repeated for all side
members 102 so the side members 102 form a closed periphery.
After assembly, the truss member 100 can be expanded for use or
folded into a substantially flat folded configuration for storage
or transport. FIG. 4 illustrates an end view of a partially folded
truss member 100. The truss member 100 is folded by moving the side
members 102 in the directions indicated by the curved arrows in
FIG. 4. While being folded, the adjacent side members 102 rotate
relative to each other at the edges of the side members 102 joined
by the hinge members 108. Expanding the truss member 100 to the
deployed configuration involves moving the side members 102 in
directions opposite those indicated by the curved arrows and
installing a locking frame 110 to retain the truss member in the
deployed orientation.
FIG. 5 shows details of the locking frame 110 used to achieve
rigidity of the assembled truss member 100. The locking frame 110
in FIG. 5 is a rigid frame having four sides 504 and four corners
506. Cross bracing 508 may be included for added strength. The
locking members 112 in this embodiment are formed as posts that
protrude generally perpendicular to a plane defined by the four
sides 504. The locking frame 100 is attached by inserting the
locking members 112 of the locking frame 110 into the receiving
ends 114 of the truss member 100. Locking holes 502 are included in
the locking members 112. The locking holes 502 align with locking
holes 503 on the support members 104 (best seen in FIGS. 1 and 2).
An interference member (not shown) can be passed through holes 502,
503 to lock the truss member 100 to the locking frame 110.
FIG. 6 is a partial view of a display structure 400 created by
connecting two truss members 100 to a locking frame 110. The first
and second truss members 100 are expanded to the deployed
configuration. The locking frame 110 is inserted into the receiving
ends 114 on the lower edges 101 of the first truss members 100. The
second truss member 100 is similarly attached to the locking frame
110 and thereby rigidly coupled to the first truss member 100.
A fastening member (e.g. interference member) 602 can be used to
create a positive locking engagement between the locking frame 110
and the truss members 100. The mounting holes 502, 503 are aligned
such that fastening members 602 can be placed through the holes
502, 503. In this example, exemplary fastening members 602 include
a quick release pin 604, a welded locknut/screw assembly 606 and a
nut/bolt assembly 608. Other fastening members 602 such as clips,
rivets, wire ties, snaps, latches, clamps, and etc., may also be
used to fasten the truss members 100 and the locking frames
110.
In some display structures 400, the truss members 100 have
sufficient strength to preclude the need for a locking member 110
at every junction. At those junctions, the display structure 400
may be connected by placing independent (i.e. not interconnected)
locking members 112 between the receiving ends 114. Independent
locking members 112 may also be fixed with fastening members 602,
as described herein above.
The truss member 100 and display structure 400 according to the
present invention can be beneficially be adapted for all manner of
structural uses, particularly those of a temporary or seasonal
nature. In particular, one such configuration desirable for uses
such as displays or point of sale fixtures is described herein in
detail. A truss member 100 having approximately 12''.times.12''
cross sectional dimensions is preferable in these applications. The
individual truss member lengths can vary from about 6'' to about
80''. The support members 102 are formed from 3/4'' to 1'' square
steel tubing welded to 3/16'' wire lacing forming the bridging
members 106. The hinge members 108 are investment cast from steel
and finished with a smooth finish along the hinge channel surfaces
306. Fabricating the truss assembly 100 from steel offers
advantages of low cost, high strength, and magnetic properties for
easy attachment of magnetic graphics. The steel is typically powder
coated for appearance and corrosion resistance. The support members
can be of different sizes and of different materials than stated
above, such as round tubes and plastics, aluminum or other
materials with sufficient strength. In general, the strength of
coupled truss members 100 in this specific application should be
able to be safely used over a 40 foot span with no load. Loads up
to a few hundred pounds can be supported either applied centrally
or distributed. Such load bearing capability would enable the truss
to safely support item such as computer or TV monitors, lights and
signage, typically used in an exhibit/display. The weight of the
truss member 100 so configured will range from 1/2 pound to 10 lbs
for truss lengths between 6'' and 80''.
The foregoing objects, advantages and distinctions of the
invention, among others, are obtained in a presently preferred
construction that provides a portable support structures for use in
temporary fixtures such as trade shows and conventions, and
particularly to a portable folding truss system having hinging side
elements.
The foregoing description of the exemplary embodiment of the
invention has been presented for the purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise form disclosed. Many modifications and
variations are possible in light of the above teaching. It is
intended that the scope of the invention be limited not with this
detailed description, but rather by the claims appended hereto.
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